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PARAMETRIC STUDY ON THE THRUST OF BUBBLY WATER RAMJET WITH A CONVERGING-DIVERGING NOZZLE

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Journal of Hydrodynamics 2009年第5期21卷 591-599页

作者： FU ying-jie WEI ying-jie ZHANG Jia-zhong School of Astronautics Harbin Institute of Technology Harbin 150001 China

To predict the thrust of bubbly water ramjet with a converging-diverging nozzle, the physical processes occurring in the diffuser, mixing chamber and nozzle were analyzed. The mathematical models were constructed separately under the restrictions of certain assumptions. The bubbly nozzle flow was examined using a two-fluid model and accomplished by specifying the water velocity distribution in the nozzle. The numerical analysis of flow field in the nozzle shows that the Mach number at the throat is 1.009, near unity, and supersonic bubble flow appears behind the throat. There is greater thrust produced by bubbly water ramjet, compared with single-phase air ramjets. Subsequently, the influences of vessel velocity, air mass flow rate, inlet area Ai, area ratio （i.e., mixing chamber to inlet area Am/Ai）, and initial bubble radius on the thrust were emphatically investigated. Results indicate that the thrust increases with the increase of air mass flow rate, inlet area and the area ratio, and the decrease of initial bubble radius. However, the thrust weakly depends on the vessel velocity. These analytical and numerical results are useful for further investigation of bubbly water ramjet engine.

关键词： bubbly water ramjet converging-diverging nozzle bubbly flow ramjet thrust numerical simulation

Nanowires:Synthesis and Energy/Environmental Applications

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Energy & Environmental Materials 2021年第4期4卷 544-561页

作者： Heng Li ying-jie Zhu State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

As the main inorganic component of human bones and teeth,hydroxyapatite(HAP)materials have been widely investigated for various applications especially in the biomedical ***,HAP nanowires(HAP NWs)have attracted research interest in the energy and environment-related fields owing to their advantages such as excellent biocompatibility and bioactivity,high-thermal stability,surface modification and functionalization,and selfassembly to form nanoscale porous networked *** this review,we first briefly discuss the synthesis of HAP *** we focus on summarizing the foremost advances in energy and environment-related applications of HAP NWs,including the battery,solar energy-assisted water evaporation,light-driven self-propelled device,thermal insulation,fireresistant inorganic paper,water purification,air purification,molecular detection,superhydrophobic surface,and high-strength nanocomposite *** addition,the future research directions on HAP NWs and their energy and environmental applications are *** review aims to provide inspiration and stimulate extensive future studies in the energy and environmental applications of HAP NWs and other inorganic NWs.

关键词： hydroxyapatite nanowire application energy environment

Nanostructured Materials of Calcium Phosphates and Calcium Silicates： Synthesis, Properties and Applications

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Chinese Journal of Chemistry 2017年第6期35卷 769-790页

作者： ying-jie Zhu State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 200050 China

Calcium phosphates are a family of compounds with different chemical compositions, structures and properties containing calcium ions and functional groups of orthophosphate （ pO34- ）, metaphosphate （ PO3- ） or pyrophosphate （ P2O4-7 ） and sometimes hydrogen or hydroxide ions. Calcium phosphates can be widely found in nature as well as in hard tissues （bone and tooth） of the vertebrate. Owing to similar chemical composition and structure to the main inorganic constituents of bone and tooth, calcium phosphate-based materials are promising biomaterials with high biocompatibility, and have been investigated for applications in various biomedical areas. Calcium silicate-based materials have attracted much attention on their potential applications in various biomedical fields such as bone de- fect repair and drug delivery. In recent years, this research group has been focusing on the research in this exciting and rapidly evolving research field, and has published many papers. This article will provide a brief review on our main research work on the synthesis, characterization, properties and applications of nanostructured materials of calcium phosphates and calcium silicates. Finally, future perspectives and challenges for the research and applica- tions of nanostructured materials of calcium phosphates and calcium silicates are discussed.

关键词： calcium phosphate calcium silicate nanostructured materials biomaterials biomedical applications

Bioinspired flexible,high-strength,and versatile hydrogel with the fiberboard-and-mortar hierarchically ordered structure

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Nano Research 2021年第10期14卷 3643-3652页

作者： Han-Ping Yu ying-jie Zhu State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

The synthetic hydrogels with high water contents are promising for various applications,however,they usually exhibit low mechanical *** this work,inspired by the natural biological soft tissues,whose hierarchically ordered fibrous structures result in high strength and good flexibility,a flexible,high-strength,and versatile hydrogel with the fiberboard-and-mortar hierarchically ordered structure(HFMOS)is developed based on ultralong hydroxyapatite(HAP)nanowires and polyacrylic acid(PAA).The as-prepared HFMOS hydrogel has a high water content(~70 wt.%),dense structure,and excellent mechanical properties,and these properties are similar to those of the human cartilage and are superior to many hydrogels reported in the *** excellent mechanical properties of the HFMOS hydrogel originate from the combination of the fiberboard-and-mortar hierarchically ordered structure,reinforcement of ultralong HAP nanowires,strong interfacial strength,and multiple energy dissipation ***,thanks to the controllable components and injection procedure,the HFMOS hydrogel with a Janus structure is prepared for particular *** HFMOS hydrogel possesses abundant ordered water channels,and can be used for loading,release,and directed delivery of various functional ***,the as-prepared flexible,high-strength,and versatile HFMOS hydrogel possesses a great potential for various applications such as water purification,pollution treatment,biomedicine,nanofluidic devices,and high-performance structural materials.

关键词： hydrogel nanowire hydroxyapatite ordered structure

An Electrochemically Stable 2D Covalent Organic Framework for High-performance Organic Supercapacitors

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Chinese Journal of Polymer Science 2020年第5期38卷 558-564,I0008页

作者： Rashid Iqbal Amir Badshah ying-jie Ma Lin-jie Zhi CAS Key Laboratory of Nanosystem and Hierarchical Fabrication National Center for Nanoscience and TechnologyBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Department of chemistry Kohat University of Science and TechnologyKhyber PakhtunkhwaPakistan

An electrochemically stable two-dimensional covalent organic framework,PI-COF,has been synthesized by a scalable solvothermal ***-COF possesses a highly crystalline structure,well-defined pores,high specific surface area,and cluster *** to these features,PI-COF can work as electrode materials in organic supercapacitors,exhibiting a specific capacitance of 163 F/g at 0.5 A/g over a wide potential window of 0-2.5 ***,PI-COF shows excellent rate performance,which can deliver 96 F/g even at a high current density of 40 A/*** of the high capacitance and wide potential window,PI-COF has achieved a superior energy density of 35.7 W h/kg at a power density of 250 W/*** importantly,due to the remarkable electrochemical stability,the PI-COF based device shows outstanding cycling stability with 84.1%capacitance maintained(137 F/g)after 3.0×10^4 charged/discharged cycles at 1 A/*** work should shed light on designing new COF-based electrode materials for and other electrochemical devices.

关键词： 2D COFs Electrochemically stable Electrode materials High energy density Organic supercapacitors

Ultrasound Imaging of Pipeline Crack Based on Composite Transducer Array

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Chinese Journal of Mechanical Engineering 2018年第5期31卷 25-34页

作者： Shou-Peng Song ying-jie Ni Department of Instrument Science and Engineering School of Mechanical Engineering Jiangsu University

Cracks, especially small cracks are di cult to be detected in oil and gas transportation pipelines buried underground or covered with layers of material by using the traditional ultrasonic inspection techniques. Therefore, a new com?posite ultrasonic transducer array with three acoustic beam incidence modes is developed. The space model of the array is also established to obtain the defect reflection point location. And the crack ultrasound image is thus formed through a series of small cubical elements expanded around the point locations by using the projection of binariza?tion values extracted from the received ultrasonic echo signals. Laboratory experiments are performed on a pipeline sample with di erent types of cracks to verify the e ectiveness and performance of the proposed technique. From the image, the presence of small cracks can be clearly observed, in addition to the sizes and orientations of the cracks. The proposed technique can not only inspect common flaws, but also detect cracks with various orientations, which is helpful for defect evaluation in pipeline testing.

关键词： Composite transducer array Ultrasound imaging Crack NDT&E

Determination of trace gadolinium by catalytic kinetic fluorimetry

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Rare Metals 2015年第8期34卷 595-599页

作者： Juan-Ping Chen Yu-ying Liu ying-jie Gao School of Chemical Engineering Shandong University of Technology

There was a significant catalytic effect of trace Gd(III) ions on the oxidative reaction of potassium persulfate with Saffron T in the acetic acid–sodium acetate buffer solution. Thus, a catalytic kinetic fluorimetry method for the determination of trace Gd(III) ions was established. The factors such as acidity, concentration of reagents, reaction time, and temperature as well as influence of coexisting ions were discussed. The optimum reaction conditions were established. The apparent rate constant and apparent activation energy of the reaction were determined. The linear range is 0.02–0.10 lgáml-1,and the detection limit is 7.27 9 10-4lgáml-1. This method was used for the determination of gadolinium in the samples of lanthanum acetate with RSD of 0.9 %–3.1 %.

关键词： Gadolinium Catalytic kinetic fluorimetry Saffron T

Exploration of the regulatory effect of miR-21 on breast cancer cell line proliferation and invasion as well as the downstream target genes

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Asian Pacific Journal of Tropical Medicine 2016年第5期9卷 456-459页

作者： ying Kuang ying-jie Nie Central Lab Guizhou Provincial People's Hospital

Objective: To study the regulatory effects of miR-21 on breast cancer cell line proliferation and invasion as well as the downstream target genes. Methods: Breast cancer cell lines MCF-7 were cultured and transfected with miR-21 mimics and the corresponding negative control mimics(NC mimics), and then MTS kits were used to detect cell viability. Transwell experiment was used to detect cell invasion ability, and fluorescence quantitative PCR was used to detect the expression of proliferation and invasion-related genes in cells. Results: 24 h after transfection of miR-21 mimics and NC mimics, cell OD value and the number of invasive cells of miR-21 group were significantly higher than those of NC group, and m RNA contents of PDCD-4, Fas L, PTEN, Rho B, Maspin, TIMP3 and RECK in cells were significantly lower than those of NC group. Conclusion: miR-21 can promote the proliferation and invasion of breast cancer cell lines, and its downstream target genes include PDCD-4, Fas L, PTEN, Rho B, Maspin, TIMP3 and RECK.

关键词： Breast cancer Micro RNA Proliferation Invasion

AMCheX: Accurate Analysis of Missing-Check Bugs for Linux Kernel

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Journal of Computer Science & Technology 2021年第6期36卷 1325-1341页

作者： ying-jie Wang Liang-Ze Yin Wei Dong Key Laboratory of Software Engineering for Complex Systems College of Computer Science National University of Defense TechnologyChangsha 410073China

The Linux kernel adopts a large number of security checks to prevent security-sensitive operations from being executed under unsafe *** a security-sensitive operation is unchecked,a missing-check issue *** check is a class of severe bugs in software programs especially in operating system kernels,which may cause a variety of security issues,such as out-of-bound accesses,permission bypasses,and privilege *** to the lack of security specifications,how to automatically identify security-sensitive operations and their required security checks in the Linux kernel becomes a challenge for missing-check *** this paper,we present an accurate missing-check analysis method for Linux kernel,which can automatically infer possible security-sensitive ***,we first automatically identify all possible security check functions of *** according to their callsites,a two-direction analysis method is leveraged to identify possible security-sensitive operations.A missing-check bug is reported when the security-sensitive operation is not protected by its corresponding security *** have implemented our method as a tool,named AMCheX,on top of the LLVM(Low Level Virtual Machine)framework and evaluated it on the Linux *** reported 12 new missing-check bugs which can cause security *** of them have been confirmed by Linux maintainers.

关键词： security check function security-sensitive operation program analysis missing-check